Patent · US Expired

Toner and image forming method

US6447969B1 · kind B1 · utility

22Cited by
24References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 2000
Grant dateSep 10, 2002
Priority date
Expiry dateMay 30, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/0825
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A toner is formed of toner particles each comprising a binder resin and iron oxide particles dispersed therein. The toner particles are characterized by uniform but non-surface-exposed dispersion of the iron oxide particles within the toner particles as represented by (i) a carbon content (A) and an iron content (B) giving a ratio B/A<0.001 at surfaces of the toner particles as measured by X-ray photoelectron spectroscopy, (ii) an average circularity of at least 0.970, and (iii) at least 50% by number of toner particles satisfying D/C&lE;0.02, wherein C denotes a projection area-equivalent circular diameter of each toner particle and D denotes a minimum distance of iron oxide particles from a surface of the toner particle, based on a sectional view of the toner particle as observed through a transmission electron microscope (TEM).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.